I can't figure out the password for lvl_2.zip. I did manage to find its contents by looking in the actual game files, but that didn't help me at all. What should I do?

If you look closely to the glitched picture, it said "password in clipboard" which means you have to paste the password.
We know it's not really clear. The new version of the game, coming in few days, make it more obvious.
Anyway, thank you for testing our game ! :)